[Zubeneschamali]

Originally Posted by Max Power1

miles/tank is not valid as the tank is not constant between cars! FFS

Its MPG (or l/km if you really must )

My car does 6 light years per cubic mile of diesel.

[Gophur]

Who ever fills up his/her car with the same amount each time?

[Swanner]

Jesus lads it's not rocket science.

2 cars with 60 litre tanks. One goes 400 miles on a full tank. The other one goes 300 miles. The first car is getting an extra 100 miles out of the same amount of juice and is therefore more economical. Simples.

As I said above, unless the tanks are the same capacity, the comparison is irrelevant and measuring economy this way is pointless.

If, like myself and op, you are comparing cars that you have owned with the same tank capacity then this seems like a reasonable way to compare economy and it's certainly more reliable then trusting the mpg reading on your car.

To be honest, I don't really care what the mpg is, I just want to know if I'm spending more or less then before.

You may not like that we choose to do it this way, that's your call but arguing that it's not a valid measurement is quite simply incorrect and shows that your not grasping the concept.

[Max Power1]

Originally Posted by Swanner

Jesus lads it's not rocket science.

2 cars with 60 litre tanks. One goes 400 miles on a full tank. The other one goes 300 miles. The first car is getting an extra 100 miles out of the same amount of juice and is therefore more economical. Simples.

As I said above, unless the tanks are the same capacity, the comparison is irrelevant and measuring economy this way is pointless.

If, like myself and op, you are comparing cars that you have owned with the same tank capacity then this seems like a reasonable way to compare economy and it's certainly more reliable then trusting the mpg reading on your car.

To be honest, I don't really care what the mpg is, I just want to know if I'm spending more or less then before.

You may not like that we choose to do it this way, that's your call but arguing that it's not a valid measurement is quite simply incorrect and shows that your not grasping the concept.

Im sorry, but !

Im not grasping the concept?? Fine then, you continue measuring in Litres/Tank and see where it gets you.

[Swanner]

Originally Posted by Max Power1

Im sorry, but !

Im not grasping the concept?? Fine then, you continue measuring in Litres/Tank and see where it gets you.

Again...failing to grasp a simple concept.

It's not litres/tank. It's miles/tank or miles/60 litres.

And as it's a valid measurement that's served me well for my last 4 cars, I will stick to it thanks.

[trout]

To answer the OP ... I get 30 MPG on average from a C180K, doing mostly city driving. On a motorway, with a gentle foot, this can be slightly better, around 35 mpg.

A fill up from empty is about 75 euro.

[Alanstrainor]

Originally Posted by Swanner

Again...failing to grasp a simple concept.

It's not litres/tank. It's miles/tank or miles/60 litres.

And as it's a valid measurement that's served me well for my last 4 cars, I will stick to it thanks.

You're right. Your calculation is not rocket science. But MPG or l/100km is a far better way of measuring fuel consumption, as it doesn't depend on the tank size remaining constant. As had been said the capacity of fuel tanks changes from car to car.

And to confuse your calculation more, you are assuming you use your full 60 litres in between fills. I'd bet there'd be 4/5 litres left in the tank when you fill up.

[shedweller]

Originally Posted by Swanner

And as it's a valid measurement that's served me well for my last 4 cars, I will stick to it thanks.

You are perfectly entitled to use that system.

The reason i don't use the miles/ km per tank system is that if i change car and its fuel tank is a different size then does that mean my mpg is different? Maybe so, but not because the tank is smaller or bigger.

Anyone remember Jeremy Clarkson driving to Scotland in an audi? If i remember correctly he did it in one tank. Amazing you would think, until it is pointed out that the fuel tank in the car in question is massive. I think his mpg was in the 40's. Which isn't so impressive. Well, it hardly justified a whole section of the top gear show.

[Swanner]

I agree. As an industry recognised measurement, mpg or Litres/100 km make total sense as you're comparing cars of all different shapes, sizes, fuels and tank capacities.

In the vein of this thread though the op is measuring like with like. Likeiwse it just so happens that my last 4 cars had 60L tanks and so I compared them that way.

I also agree that miles/tank isn't 100% accurate but anyone who's measuring that way is probably only looking for a rough guide and from full tank to red line or petrol light on will be there or thereabouts.

On the downside the new 523i is over halfway between 3/4 and 1/2 and only reading 120 miles. It's got a bit of making up to do to get over the magic 320 mark And i've been taking it very handy.